dlang windows api threads example

import core.stdc.stdio;
import core.sys.windows.windows;

struct UserData {
    int data;
}

extern (Windows) uint t1(void* data) {
    auto tid = GetCurrentThreadId();
    auto dt = *(cast(UserData*)data);
    auto myint = dt.data;

    foreach(i; 0..3){
        printf("from thread %i: %i \n", tid, myint);
        Sleep(1000);
    }
  return 0;
}

extern (Windows) uint t2(void* data) {
    auto tid = GetCurrentThreadId();
    auto dt = *(cast(UserData*)data);
    auto myint = dt.data + 1;

    foreach(i; 0..3){
        printf("from thread %i: %i \n", tid, myint);
        Sleep(1000);
    }
  return 0;
}

extern (Windows) uint t3(void* data) {
    auto tid = GetCurrentThreadId();
    auto dt = *(cast(UserData*)data);
    auto myint = dt.data + 2;

    foreach(i; 0..3){
        printf("from thread %i: %i \n", tid, myint);
        Sleep(1000);
    }
  return 0;
}

extern (C) int main() @nogc nothrow {
    uint[3] tid;
    HANDLE[3] Array_Of_Thread_Handles;


    auto ud1 = UserData(5);
    auto ud2 = UserData(5);
    auto ud3 = UserData(5);

    Array_Of_Thread_Handles[0] = CreateThread(null, 0, &t1, &ud1, 0, &tid[0]);
    Array_Of_Thread_Handles[1] = CreateThread(null, 0, &t2, &ud2, 0, &tid[1]);
    Array_Of_Thread_Handles[2] = CreateThread(null, 0, &t3, &ud3, 0, &tid[2]);

    WaitForMultipleObjects( 3, Array_Of_Thread_Handles.ptr, true, INFINITE);

    printf("gg".ptr);

    CloseHandle(Array_Of_Thread_Handles[0]);
    CloseHandle(Array_Of_Thread_Handles[1]);
    CloseHandle(Array_Of_Thread_Handles[2]);

    return 0;
}